钻孔瓦斯流量法确定煤层渗透率和瓦斯压力的试验研究

Test of Coal-seam Permeability and Methane Pressure by Bore-hole Methane Flow Method

针对煤矿生产实践中存在测定煤层渗透率和瓦斯压力难度大、准确率低的问题,依据煤层瓦斯径向流动原理,构建了用于确定煤层渗透率和瓦斯压力的理论和方法,并在五阳煤矿进行了不同钻孔直径和不同流量监测时间段的实测对比。结果表明:钻孔直径对煤层渗透率和瓦斯压力的计算值影响较小;瓦斯流量监测时间段对煤层渗透率和瓦斯压力的计算值影响较为显著,进行q-1-lnt图线性回归分析,为减少误差应选用钻孔施工5d后的流量数据;计算值与实测值相比误差较小,能够满足矿井瓦斯灾害预测和防治中对瓦斯基础参数的测定要求。

It is difficult that measuring coal-seam permeability and methane pressure and measurement accuracy is low. This paper constructed theory and method of determining coal-seam permeability and methane pressure on the basis of methane racial flow principle. On-the-spot measurement with different bore-hole diameters and different flow was finished in Wuyang Colliery. Results showed that the influence of bore-hole diameter on calculation value of coal-seam permeability and methane pressure was small,but that of methane flow monitoring time was obvious. Flow data after 5 days of bore-hole construction should be selected for linear regression analysis to reduce error. Relative error of calculation value and measurement value was small,which showed that this method could meet the requirement of basic methane parameter in methane prediction and prevention.